Doughnut sugaring machine



Jan. 2, 1951 E. J. ROTH 2,536,652

' DOUGHNUT SUGARING MACHINE Filed July 17, 1946 3 Sheets-Sheet 1 "-7- INVENT 96 94 96 ErnesZJKoih 2 ATT EY I Jan. 2, 1951 J ROTH 2,536,662

DOUGHNUT SUGARING MACHINE Filed July 17, 1946 5 Sheets-Sheet 2 E INVENTOR Ernest? J Roi/1 Patented Jan. 2, 1951 DOUGHNUT' SUGARING MACHINE Ernest Roth, Rockleigh, N. 5;, assignor'to'Joe Lowe Corporation, New York, N; Y., a-corporation of Delaware Application July-17, 1946; Serial No. 684,321

(oral-7 5 Claims.

The: present invention relates generally to apparatus: for coating articles" with pulverized or 'granul'anmaterials; and; while it isapplicable to many other" uses, it is more specifically concerned with the coating or dusting of bakery products,

such: as: cakes; crullers, cookies, doughnuts and the like; with dry powdery sugar or materials having similar physioah characteristics.

An object ofthepresent. invention is to pro-- vide' a simple,v inexpensive: and: economical apparatus for applying-iazuniform-coating to articles off the character described. in a rapid. efficient,

economicali and: continuous manner without dani- 'ger of v damaging said: articles; applying an, in-

complete or non-uniform coating thereto, or wastingsaidcoating materiall further object of the invention is the provisionof? simple; inexpensive and; efficient appa-ratuswhich permits the safe and efficient handling: of large numbersof such products simultansously'and;oontinuouslm andiwhich is capable of uniformly controlling: the amount of coating or. dusting: material? contacting the bakery products;

Another. object oi"v the invention is to provide meansiorpositively tumbling said articles in an efiicient and' non-injurious manner to cause an application of said coating materialtoiall exterior surfaces" of said": products during each tumbling operation in. an efi'icient and uniform manner.

A furth r object of the invention: isv the provision: of suitable means for continuously feedin; thecoating or dustinglmaterial from a. reserve reservoir or hopper'to the tumbling drum in a uniform: and eificient manner, and for removing the unusedorexcess coating, or dusting, material therefronr.

Anotherobject of theinventionzis to providea coating apparatus of: the character described having all of its moving parts suitably enclosed so: as: to eliminate the danger of; accidents. and the like and to protect the-apparatus audit-s edible contents fromdust,, dirt, etc.

A. further objectof the invention is the:pro'- vision: of novel means for insuring uniform delivery of the coating, or dusting, material from a combination reserve reservoir and collecting bin to a rotatable coating drum in a fine powdery stream.

Various other and further objects and advantages oi: the inventiomwhich result in simplicity,'

economy and efliciency; willbe apparent from the following detailed description, wherein a preferred form of embodiment of" the invention is shoum', reference: being had for illustrative pur'a 2, poses tothe accompanying drawings, forming. a part. hereof; in which:

Figure l? is. a side elevational' View of an apparatus constructed in accordance with" the invention; withza part" being in. section in order: to show the lower drive mechanism for operating the rotating inner: drum, vibrator and lump breaker mechanism;

Figure 2 is at top-plan, view of the apparatus showniirr Figure l, with the housing for" the upper drive mechanismbeing in section in order: to: illustrate'the' driving mechanism for the elevator for conveying the coating or dusting material from it's reserve reservoir to the top of the apparatus and the cooperating lateral feed screw conveyor for delivering said material into the rotating coating. or dusting drum;

Figuret is a' rear elevational View of the apparatuss-hownin Figure 1, with the upperdriving mechanism, including the lateral screw-feed conveyor being shown partly in section;

Figure- 4 is a fragmentary longitudinal sectional View of the apparatus shownin Figure 2, the same being taken substantially along the line 44 thereof, looking'in the direction of the arrows; and illustrating the detailed construction of the inner and outer drums;

Figure 5 is a cross-sectional view of the apparatus shown in Figure'l, the'samehaving been "taken substantially along the line 55- thereof,

looking in the direction of the arrows, and illustratingthe details of the collecting bin-and reserve reservoir, and the driving mechanism for the lump breaker and vibrator;

Figure 6 is a: fragmentary sectional View of the apparatus shown in Figure 3, the same having been taken substantially along the line 66 thereof; looking in the direction of the arrows, and illustrating the details of construction of the reserve reservoir; its lump breaker and its delivery elevator; and

Figure? isa fragmentary sectional view taken substantially along the line T-T of Figure 6, showingingreater detail the features of the lump breaking mechanism of the reserve reservoir;

Referring now to' the drawings, and particularly to Figure 1 thereof, there is shown a boxlilre supporting structure ill consisting of a plurality of legs H- suitablyconnected and braced intermediatetheir ends by horizontal cross-bars t2; A stationary outer cylindrically-shaped drum 8:4 is fixedly secured on the tops of the legs H, having an inlet or receiving opening. is at one end and an outlet or discharge opening l8-at the PE QSEB" 6. 131- .A sloping open-topreceiving chute through its perforations 34.

20 is mounted on the outside of the drum I4 adjacent the inlet or receiving opening l6, and is suitably braced by a supporting bracket 2I. A similar discharge chute 22 is mounted adjacent the outlet or discharge opening I8. Suitable conveyors (not shown) are employed for conveying articles to be coated to the inlet or receiving chute 26 and to receive and carry away the coated articles discharged by the outlet or discharge chute 22. A rotatable shaft- 24 is mounted axially of the drum I4 in suitable bearing blocks 26 secured to the outer sides of the respective ends thereof.

A rotatable inner drum 30 is mounted fixedly on the shaft 24 by means of a series of longitudinally spaced spiders 32, one of which is shown in Figure 5. The inner drum 30 is of a solid construction adjacent the inlet or article receiving end, and a section thereof adjacent its discharge or delivery end is perforated, as indicated at 34, to provide means for gravitationally discharging any excess or unused granular coating material (not shown) therefrom. The discharge end of the inner rotatable drum 30 is provided with an outwardly flaring flange 36 (see Figure 4) to provide a suitable discharge connection with the discharge chute 22 mounted on the outer side of the discharge end of the outer drum I4. Means in the form of a fixed spiral tubular rod or vane '40 is mounted concentrically within the inner rotating drum 30, and is spot-welded or other wise securely connected to said drum 30 at suitably spaced intervals. The several adjacent convolutions of the vane 40 are connected longitudinally and circumferentially at suitable spaced intervals by relatively short brace rods 42, which are securely welded thereto. The spiral vane 49 causes the articles deposited in the inner drum 30 at the inlet end I6 to be fed longitudinally there- -through and to be discharged therefrom through the discharge outlet I8 when the inner drum 30 is rotated, and the circumferentially spaced longitudinal brace rods 42 cause the articles to be tumbled over and over again in their passage through said revolving inner drum 30.

An opening 44 is formed in the bottom of the outer drum I4 below the perforations 34 of the inner drum 30, and, by turning down the metal of the outer drum 14 adjacent said opening, vertical depending flanges 46 are formed about said opem'ng 44 to provide a suitable delivery chute, as best shown in Figure 5. A suitable sloping member 41 is welded to the bottom of the depending flanges of the chute 46, as indicated at 46, to form a sloping bin or gravity collecting means 49 for receiving the unused coating material discharged from the rotating inner drum 30 An opening 50 is out in one side of the chute 46, which is closed by means of a trap door swingably mounted on hinges 52. The door 5| permits inspection and cleaning of the collecting bin 49. A reserve reservoir 54 is mounted adjacent the base of the collecting bin 49, having one side integrally formed with the sloping bottom 41 there- 'of, and is provided with a top cover member 56 swingably mounted on hinges 58 to permit inspection, filling and cleaning out of the same.

It will be noted that the collecting bin 49 and reserve reservoir 54 have a common discharge trough 60 in the bottom thereof. The top of said discharge trough 60 is provided with a closure plate 62, having a series of transversely extending longitudinally spaced slots 64 therethrough (see 'Figures 6 and 7). A shaft 66 is mounted thro g the sides of the reservoir 54 in alignment with and directly above the trough 60. The shaft 66 has reduced end bearing sections 68 and I0, which extend through the sides of the reservoir 54. The bearing section 66 is suitably journalled in a bearing block I2 mounted on the outside of the reservoir 54. The reduced bearing section I0 is journalled in a bearing block '54 mounted on a fixed depending vertical bracket I5 welded to the outside of the opposite side of the reservoir 54. A spring 16 is mounted on the bearing section 10 between the outside of the reservoir 54 and the bracket 15, which serves to hold the shaft 66 in a fixed position longitudinally. The bearing section '69 projects entirely through the bearing block I4 and has a sprocket wheel "I8 keyed to its outer end for driving the same. A second bearing block I9 is mounted on the supporting leg I2 for receiving the projecting end of the bearing section I0 of the shaft 66. The enlarged central section of the shaft 66 carries a series of fixed circumferentially spaced radial fingers arranged in rows longitudinally thereof, which are of sufficient length to project a short distance through the slots 64 of the plate 62. The spring #6 prevents end play in the shaft 66 and maintains the fingers 80 in proper operating alignment with their respective slots 64 of the top closure plate 62 for the trough 60,

An endless conveyor or elevator 82 operates in the trough 89, and consists of a chain of substantially square-shaped interlocking links 84 having transversely spaced cross-bars 86 welded thereto at longitudinally spaced intervals. The conveyor or elevator 82 extends over an idler sprocket wheel 81, which is best shown in Figure 6. The idler sprocket wheel 81 is keyed to a shaft 83 extending transversely of the trough 69 adjacent its outer end. The shaft 88 is mounted in bearing blocks 90 secured to the sides of the trough 60. A conventional screw take-up or adjustment is provided for the shaft 83, as indicated at 92 (see Figure 1), and affords suitable means for varying the tension on the chain 84. The conveyor or elevator 82 extends from the lower end of the trough 60 to the upper opposite end of the apparatus,as best shown in Figure 1, and is enclosed throughout its entire length by a removable sectional housing 94, which confines the dry powdery coating material therein and also serves to keep out dirt, dust, etc. The sections of the housing 94 are each provided with radial end flanges 96, which are secured together by bolts 68. An internal tubular guideway or spacer I09, which is best shown in Figure 6, is mounted in the trough 60 and within the housing 94 between the inner sides of the endless conveyor or elevator chain 84. The spacer I00 serves to maintain the chain 84 in its proper alignment in making the turn where there is a normal tendency for it to Sag or run out of alignment. The upper end of the elevator 82 operates over a suitable driving sprocket wheel I02.

A trough I64 extends laterally of the supporting structure I0 immediately below the upper or discharge end of the elevator 82 to the receiving chute 20 of the drum I4. A shaft I06 is mounted axially of the trough I04, and is journalled in suitable bearing blocks I08 and H0 mounted on the opposite ends thereof. The shaft I06 projects through and beyond the bearing block H0, and has a driving sprocket wheel II2 mounted thereon, the outer free end of the shaft I06, projecting beyond the driving sprocket wheel H2, is

'journalled in a suitable bearing block H4. The

5 trough I04; is provided with a fixed. spiral feed: screw vane M6,. which, when the shaft- I06 is rotated", serves to: feed; or convey the pulverent coating: material" deposited. in the outer' receiving end-thereon by the conveyor or elevator 82 into the open chute 29, through a suitable discharge opening H5 in its bottom, in a uniform endless stream, whereupon it :gravitates into the rotating inner: drum to through its receiving opening I6.

Referring nowto Figures 2 and 3- of: the drawings; a= singlerdrive'mechanism; which ismounted om topofi the drum: I4 adjacent it's receiving; end, isemployedto operate the: conveyor'orelevator 82 and: the lateral feed: screw 6- for moving the coating. material. from the reserve reservoir. 54 to the receiving: chute 2e; in a uniform endless stream. This driving; mechanism is enclosed in: a

suitable" conventional: housing Ii 8;. and consists? of .a" constant speed electric: motor I'll-0 having. an adjustable variable speed pulley I22 of conven tional construction mounted on the projecting end of. its; drive shaft- I24'. The variable speed pulley" I22 drives a belt I22 5 connect'ed'with a: driving; pulley I28 fixedly mounted. on. a driveshaft F311 ofaconventional'reduction.gear I32.v The motor: I29. is slidably mounted on the supporting structure Iii, andv is adjustable toward: and away from its reduction gear I32 by means oiashait I34; which in turn is manually operable through ai suita'ble hand whe'elf' I952 By turning'the hand I circumference, and, when. the tension is' reduced on. the driving: belt I26, it tends'to-ride higher and over a larger circumference inthe variable speed: pulley I22; Such means for varying the speed ofthe reduction gear. drive I32 isof a con;- ventiona'lconstruction, and since it forms no part of this invention nofurther' details are believed essential.

The drive shaft I38 of the reduction gear I32 extends at rightanglesto its driven shaft I30, and passes through the end: of. the housing I13" and through a bearing. block mounted on the outer end thereoflasindicated at. I46. A fixed sprocket wheel I42 is keyed tothe outer projecting end of the shaft I38; which drivesa chain I M; The

chain I44 in turn drives a sprocket wheel I46 keyed to a shaft- I48 journalled in suitable bearingblocks- I55], I5I and I52. It will be noted" that the sprocket wheel I02, which drives the. conveyor or elevator 82, is also keyed to: the shaft 138- between the-bearing blocks I5! and I52 (see Figure 2). Referring now to Figureliit will also benoted. that the-shaft I48 projects through and beyond the bearing'block I52 and carries another sprocket wheel l54-keyed thereto. The sprocket wheel- I54: drives a chain I56, which, in" turn,

drives the sprocket. wheel: H2, driving". the? shaft I 06: operating 'therlateral feed screw I I6;

Referring. now to Figures 1, 3 and 5; there? is shown a second. or lower? driving. mechanism for operating, the: rotating drum, the lump breaking mechanism and. the vibrating mechanism; This second driving mechanism consists"v of a conventional; electric motor L6H, having" a conventional variablespeed: pulley IfiZ mounted fixedly onthe proiectinea endof its drive shaitt heit- BB4 opterating over: the variable speed pulley: Hi2 drivesa pulley I66 keyed. to the shaft IGB- ofatconvtr tional. reduction. gear I111. The tension on the belt- I64 operating over the variable speed pulley Hi2 permits the regulation of the speed of the: reduction; gear H 0-,. and hence: its reduced.- driving speech The: mechanism for varying the tension Of-tITbBIti I64 is not shown, butxit isidenti'cal to that described for varying the speed: of the up per driving: mechanism hereinbe'for'e setforthz One end of the drive shaft. I6 9- of the reduc tion gear I10 is connected through: a-suitable con ventional flexible: coupling v shown diagrammatically atm with a-line shaft I14 runningilongitne dina-lly of: the supporting. structure I9; The-line:

cam conformationspos-itioned at an angle-of one hundred and eighty degrees of onean'otheir. It will be noted that the cam' comformations I94 and: I96 of the-cam I99 are mounted. onthe line shaft IM at an an gle of ninety degrees from the cam conformations I98 and 209 of the cam I92? A vibrator head 202', which: is usually made: of rubber." or some other suitable. material, is provided' for each of therotatingcams Ma a-11d I92.

Each vibrator head: 2B2! is mounted on. the-upperend of a suitable pivotalbra'cket; which consists of? a". series of interlocking; levers 294; 206, 208' and 24-9. The levers 204 and 238 are fixedly mounted on ashaft 2V2 journa'lled in bearing blocks 2 I 4' secured to the supporting'structure I 0 A spring 2ft connects thejoi'ned ends of" each of thelevers 2G6 and 298, and has its other" end secured to: the upright I I ata point spaced therebelow, as indicated at 2-l '8i Thesprings 215' tend to maintain each of? the vibrator heads 202 againstthesloping' common side or bottom ofthe collecting bin 49 and reservereservoirfl. As the cams I911 and I92 rotate with-the-line shaft I14,

their respective cam conformations I94 and I96 and I98 and 2M" strike the inwardly projecting joined ends of the lovers 2M and 296, causing the bracket topivot on its shaft 2I2 away from the bottom 4? of the reservereservoir and against the tension of the springs 216; When the cam conformations I94", I96, I93 and 2&9 each pass beyond the joined ends2ll4 andZllS- of the bracket, thesprih'gsZ I6 tend to drawn; back to its normal position, causing the vihrator head 202 to strike the bottom 41 with considerable force; thereby vibrating the same and" causing the coating material" to now freeiy down and onto the top of the slotted pIat'eB'Z. With'the cams [inland I92 having their respective cam conformations-I94 and IE6 and I98 and 209' mounted at ninety degrees-toeach other, it will" be obviousthat' one of them is always striking the bottom plate 61' at everyqua-rter' turn of the lineshaft I14, causing substantially" continuous vibrations while the apparatus' is being operated. Any" lumpy form-as tions of coating material falling onto the top of the plate-- 62 will? be unable top'a'ss through. the" slots 64' therein. Therotatihg radial fingers mounted on the shaft 66 will Break up suchl'ump formations so that the coating material thereof will pass through said slots 64.

The end of the line shaft I14 has a sprocket wheel 220 keyed thereto, which in turn drives a chain 222 that operates over the sprocket wheel .18 keyed to the shaft 66. Thus, it will be obvious that when the line shaft H4 is operating, the sprocket wheel 220 through the chain 222 will cause the sprocket wheel I8 to revolve, thereby turning the shaft 66 and causing the fingers 80 to revolve thereabout, passing in and out of the slots 64 of the plate 62.

In the operation of the apparatus, it will be assumed that the lower motor I50 has been started, driving its reduction gearing I'll which in turn causes the line shaft I14 to rotate. Rotation of the line shaft I'M causes the sprocket Wheel I82 to rotate, which through the chain I84 causes the sprocket wheel I 86 keyed to the shaft 24 to rotate the inner drum 3!]. Rotation of the line shaft I14 also drives the sprocket wheel 220, which through the chain 222 drives the sprocket wheel I8 keyed to the shaft 66, which, in turn, rotates the fixedly mounted fingers 80. The cams I95 and I92, being directly mounted on the line shaft I'M rotate with it, causing their respective vibrator heads 262 to be put into striking operation against the bottom plate 41. Thus, it will be readily apparent that the motor I60 and reduction gear I10 drive only the rotating drum 36', the rotating fingers 80 and operate the vibrator heads 202. The upper driving mechanism may now be started, which causes the motor I29 to drive'the reduction gear I32, which in turn drives the sprocket wheel I42. Rotation of the sprocket wheel I42 operates the chain I44, which, in turn, drives the sprocket wheel I46 and jack shaft I 48. Rotation of the jack shaft I48 drives the sprocket wheel I82, which, in turn, drives the elevator chain 84. Rotation of the jack shaft I48 also drives the sprocket wheel I 54, chain I56 and sprocket wheel I12 (see Figure 3), the latter driving the shaft I I I! having the spiral feed screw vanes H6 mounted thereon.

With both of the driving mechanisms in operation, it is now assumed that a quantity of coating material, such as dusting sugar, is deposited in the reserve reservoir 54 through its open door 56. The coating material will flow by gravity down onto the top of the plate 62, and some of it will pass throughthe open slots 64 therein. The revolving fingers 88 operating in the bottom section of the reservoir 54 will cause a continuous and substantially even flow of coating material through the slots 64. The material in passing through the slots 64 will fall into the trough 60 .and onto the topof the tubular spacer or guideway I00. The cross-bars B6 of the elevator 82 will cause the coating material to be swept off the end of the-guideway I00, whereupon it will fall down to the bottom of the trough 69 onto the top surface of the plate I OI. The crossbars 86 after passing around the sprocket wheel 81 will again pick up the coating material and push it along the surface of the plate IBJI to the top of the elevator 82, whereupon it is deposited in the open end of the lateral feed trough I84. When. the coating material is deposited in the feed trough I04, the spiral vanes III; of the shaft IE'S will force it to be moved therealong until it is discharged by gravity through its bottom discharge opening I I into the open top of the chute 20. Thecoating material fallinginto the chute 20 gravitates into the revolving drum 30. The spiral vanes 40 cause the coating material to be moved toward the discharge end thereof as the drum 38 is rotated, and the longitudinal brace rods 42 tend to cause the doughnuts to tumble within the drum 30 and the coating material to be carried upwardly until gravity causes it to fall down on top of the doughnuts in the form of a light spray. The excess coating material, which is that which does not adhere to the surface of the doughnuts, will pass through the apertures 34 in the rotating drum 3!) as it approaches the discharge end. The coating material passing out of the revolving drum 30 through its apertures 34 will gravitate through the chute 44 onto the sloping bottom 41, whereupon it is delivered to the reserve reservoir 54 for making another circuit of the apparatus. It will thus be observed that the coating material is kept in a uniform circulating stream, from the reserve reservoir 54 to the revolving drum 3B and back again, and that a large volume of coating material may be deposited in the apparatus without disturbing the quality of the coating operation or requiring constant watching to determine if there is enough coating material to properly dust the continuous and endless stream of articles passing therethrough.

Although I have only described and illustrated in detail one form which the invention may assume, it will be apparent to those skilled in the artthat the invention is not so limited, but that various modifications may be made therein without departing from the spirit thereof or from the scope of the appended claims.

What I claim is:

1. In apparatus of the character described, a rotatable drum having article inlet and discharge openings at opposite ends thereof and internally mounted vanes for movin articles therethrough when said drum is rotated, means for rotating said drum, said drum having a perforate section adjacent its discharge end for permitting the unused coating material to be discharged therefrom, means for collecting said unused coating material discharged from said drum, a reserve reservoir associated with said collecting means, hammer means for vibrating said reservoir, rotary cam means for causing said hammer means to strike said reserve reservoir to vibrate the same to insure a uniform free flow of coating material therefrom, means for driving said rotary cam means, and means for conveying said material flowing fro-m said reserve reservoir to the inlet end of said drum in a, uniform stream.

2. In apparatus of the character described, a rotatable drum having article inlet and discharge openings at opposite ends thereof and internally mounted vanes for moving articles therethrough when said drum is rotated, means for rotating said drum, said drum having a perforate section adjacent its discharge end for permitting the unused coating material discharged from said drum, a reserve reservoir associated with said collecting means, a plurality of hammers for vibrating said reserve reservoir and said collecting means, rotary cam means for causing said hammers to strike said reserve reservoir and said collecting means to cause the same to vibrate to insure a uniform free flow of coating material therefrom, means for driving said rotary cam means, rotary means for breaking up any lump formations of said coating material in said reserve reservoir, and means for conveying said coating material flowing from said reserve res,

ervoir to the inlet end of said drum in a uniform stream.

3. In apparatus of the character described, a rotatable drum having article inlet and discharge openings at opposite ends thereof and internally mounted vanes for moving articles therethrough when said drum is rotated, said drum having a perforate section adjacent its discharge end for permitting the unused coating material to be discharged therefrom, means for collecting said-unused coating material discharged from said drum, a reserve reservoir associated with said collectin means, means including a plurality of hammers adapted to intermittently strike the sides of said reserve reservoir to cause the same to vibrate to insure a uniform free flow of coating material therefrom, means including a plurality of spaced rotary fingers for breaking upany lump formations of said coating material in said reserve reservoir, means for operating said drum, vibrator and lump breaker, and means for conveying said coating material flowing from said reserve reservoir to the inlet end of said drum in a uniform stream.

4. In apparatus of the character described, a rotatable drum having article inlet and discharge openings at opposite ends thereof and internally mounted vanes for moving articles therethrough when said drum is rotated, said drum having a perforate section adjacent its discharge end for permitting the unused coating material to be discharged therefrom, means for gravitationally collecting said unused coating material discharged from said drum, a reserve reservoir associated with said collecting means, means including a plurality of hammers adapted to successively strike the sides of said reserve reservoir and collecting means to cause the same to vibrate to insure uniform free flow of coating material therefrom, rotary means includin a series of spaced fingers of different sizes for breaking up any lump formations of said coating material in said reserve reservoir, means for operating said drum, vibrator and lump breaker, means for conveying said coating material flowing from said reserve reservoir to the inlet end of said drum in a uni- 10 form stream, and means for operating said coating material conveying means.

5. In apparatus of the character described, a rotatable drum having article inlet and discharge openings at opposite ends thereof and internally mounted vanes for moving articles therethrough when said drum is rotated, said drum having a perforate section adjacent its discharge end for permittin the unused coating material to be discharged therefrom, means for gravitationally collecting said unused coating material discharged from said drum, a reserve reservoir associated with said collecting means, means including a plurality of cam operated hammers adapted to strike the sides of said reserve reservoir to vibrate the same to insure a uniform free flow of coating material therefrom, means including a plurality of spaced rotary fingers of different lengths for breaking up any lump formations of said coating material in said reserve reservoir and collecting means, means for Operating said drum, vibrator and lump breaker, means for con- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 945,355 Wild et al Jan. 4, 1910 1,012,877 4 Mahan Dec. 26, 1911 1,391,604 Baumgard Sept. 20, 1921 1,482,473 Lord et al Feb. 5, 1924 1,739,642 Light Dec. 17, 1929 1,819,557

Hunter Aug. 18, 1931 

